BAEL-2900 Persisting enums in JPA (#6958)

2019-05-14 21:37:28 +02:00
parent ef91212d4c
commit 0d24260e9b
8 changed files with 291 additions and 1 deletions
@@ -0,0 +1,91 @@
+package com.baeldung.jpa.enums;
+
+import javax.persistence.*;
+
+@Entity
+public class Article {
+
+    @Id
+    private int id;
+
+    private String title;
+
+    @Enumerated(EnumType.ORDINAL)
+    private Status status;
+
+    @Enumerated(EnumType.STRING)
+    private Type type;
+
+    @Basic
+    private int priorityValue;
+
+    @Transient
+    private Priority priority;
+
+    private Category category;
+
+    public Article() {
+    }
+
+    @PostLoad
+    void fillTransient() {
+        if (priorityValue > 0) {
+            this.priority = Priority.of(priorityValue);
+        }
+    }
+
+    @PrePersist
+    void fillPersistent() {
+        if (priority != null) {
+            this.priorityValue = priority.getPriority();
+        }
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public Status getStatus() {
+        return status;
+    }
+
+    public void setStatus(Status status) {
+        this.status = status;
+    }
+
+    public Type getType() {
+        return type;
+    }
+
+    public void setType(Type type) {
+        this.type = type;
+    }
+
+    public Priority getPriority() {
+        return priority;
+    }
+
+    public void setPriority(Priority priority) {
+        this.priority = priority;
+    }
+
+    public Category getCategory() {
+        return category;
+    }
+
+    public void setCategory(Category category) {
+        this.category = category;
+    }
+}
@@ -0,0 +1,17 @@
+package com.baeldung.jpa.enums;
+
+import java.util.stream.Stream;
+
+public enum Category {
+    SPORT("S"), MUSIC("M"), TECHNOLOGY("T");
+
+    private String code;
+
+    Category(String code) {
+        this.code = code;
+    }
+
+    public String getCode() {
+        return code;
+    }
+}
@@ -0,0 +1,28 @@
+package com.baeldung.jpa.enums;
+
+import javax.persistence.AttributeConverter;
+import javax.persistence.Converter;
+import java.util.stream.Stream;
+
+@Converter(autoApply = true)
+public class CategoryConverter implements AttributeConverter<Category, String> {
+    @Override
+    public String convertToDatabaseColumn(Category category) {
+        if (category == null) {
+            return null;
+        }
+        return category.getCode();
+    }
+
+    @Override
+    public Category convertToEntityAttribute(final String code) {
+        if (code == null) {
+            return null;
+        }
+
+        return Stream.of(Category.values())
+                .filter(c -> c.getCode().equals(code))
+                .findFirst()
+                .orElseThrow(IllegalArgumentException::new);
+    }
+}
@@ -0,0 +1,24 @@
+package com.baeldung.jpa.enums;
+
+import java.util.stream.Stream;
+
+public enum Priority {
+    LOW(100), MEDIUM(200), HIGH(300);
+
+    private int priority;
+
+    private Priority(int priority) {
+        this.priority = priority;
+    }
+
+    public int getPriority() {
+        return priority;
+    }
+
+    public static Priority of(int priority) {
+        return Stream.of(Priority.values())
+                .filter(p -> p.getPriority() == priority)
+                .findFirst()
+                .orElseThrow(IllegalArgumentException::new);
+    }
+}
@@ -0,0 +1,5 @@
+package com.baeldung.jpa.enums;
+
+public enum Status {
+    OPEN, REVIEW, APPROVED, REJECTED;
+}
@@ -0,0 +1,5 @@
+package com.baeldung.jpa.enums;
+
+enum Type {
+    INTERNAL, EXTERNAL;
+}